According to the U.S. CDC: "Most healthy adults may be able to infect others beginning 1 day before symptoms develop and up to 5 to 7 days after becoming sick. Children may pass the virus for longer than 7 days. Symptoms start 1 to 4 days after the virus enters the body. That means that you may be able to pass on the flu to someone else before you know you are sick, as well as while you are sick.
Some persons can be infected with the flu virus but have no symptoms.
During this time, those persons may still spread the virus to others."
According to the Center for Disease Control you are contagious for 1-4 days before you ever become sick with the flu so if you are not running fever but are still contagious before the fever comes then how can you still not be contagious for at least 5 days after you stop having fever? Evidently the flu doesnt need fever to be contagious in the beginning.
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